A tennis ball rolls horizontally to the left for 30 m at a constant speed. what is the velocity after 15 seconds? what is the speed? **PLEASE HELP - for physics, list variables

Your 249 ml cup of coffee is too hot to drink when served at 82 degree celsius. what is the mass of an ice cube taken from a -21 degree celsius freezer, that will cool your coffee to a pleasant 54 degree celsius. specific heat of the water is 4190 j/kg c, specific heat of ice is 2090 j/kg c, heat of fusion of ice is 3.33 x 10^5 j/kg

Describe the path of the electric current through a circuit?

Photons with the highest energy have the longest period